a colonial tunicate that floats in the water

A couple of weeks ago it was very common to see strange objects which looked
glass-like translucent and plastic, whilst others seemed softer, more
opaque and hairyer.  Not only were they littering the sea floor but were also driting in mid water.  On the whole the fish left them alone.

I touched one and it felt hard also as if it were made of plastic.  It was very strange.  So I emailed an image of one to our pal Andy to see if he knew what they were.

After a bit of hunting around he came back with an answer "I'm 100% sure that these tubes are Pyrosoma, and these ones
could possibly be 'Pyrosoma atlanticum".

Andy explained that my plastic tubes are also known to move and
die in large numbers and that they also use jet propulsion to move around.

Pyrosome, are colonial
tunicates that float in the water off the sea bed.

An example of a
tunicate is a sea squirt. They live mostly out in the open ocean and
can migrate a few hundred meters each day vertically. They are filter
feeders (hence the 2 holes either end). It's not too clear whether the images below have caught examples which are
alive or not… there might be some sort of a valve either end to
control filtering.

Andy suggested that the hairs on the outside might be used as
locomotion and that it might be able to use bioluminescence.

So, there you have it.  My mystery was easily explained so long as you know who to ask and how to structure the right question.

I thought the shots below were quite interesting.

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1. Anenome

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2. Pyrosome

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3. Anenome with Pyrosome

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